unfortunately you cant. you can get iphone apps that enable you to bluetooth your contacts to another iphone but not to a device that isnt produced by apple. this sort of exclusivity really sucks but as yet i havent found a way around it.
bluetooth
To connect users using reliable data and voice communication
no
you need a type of app
To put the Voice Star 17-2596 in pairing mode, you typically need to press and hold the Bluetooth pairing button on the device until the LED indicator light starts flashing rapidly. This indicates it is in pairing mode and ready to connect to other Bluetooth devices. Refer to the product manual for specific instructions.
If you purchase the iPhone 4S Siri (the voice) is automatically built in. It is not available for earlier handsets.
I would say the IPhone because the Itouch only has the ability for Wifi and apps and the basics. But the Ipone has Calling abilities and voice abilities where as the Iphone has no voice capability.
A system designed for hands free in a car setting is the best such as Kensington Hands-Free Visor Car Kit for iPhone and Bluetooth Phones
a bluetooth headset can be used to answer or make calls. may other bluetooth have more options like music, voice command and many more.
My iphone!
If you search in the Apple App store under voice changers there are voice changers apps if you wanted to make prank calls.
okk this is what you do, use another device that allows recording, sing then if your voice still sounds 'different' like on ur iphone then its you! hope that helps!